misultin: handle stream error

Hello,
I use "misultin" as http-server, and i send data by "Req:stream".
My problem: if client close browser, and i try Req:stream(ChunkData) i
get this error in log
"""
module: misultin_socket
line: 176
error sending data: closed
"""
It's normal, but how do i known this situation ("Req:stream" work
asynchronyous and return nothing) ?
Thanks!